The 3GPP (Third Generation Partnership Project), which is a standardization project, has standardized Evolved Universal Terrestrial Radio Access (hereinafter referred to as “E-UTRA”), which achieves high-speed communications, by the adoption of the OFDM (orthogonal frequency-division multiplexing) communication scheme and flexible scheduling in predetermined units of frequency and time called resource blocks.
Further, the 3GPP is also working on the standardization of an evolutionary extension of E-UTRA, i.e., Advanced E-UTRA. Advanced E-UTRA envisages using a band up to a maximum bandwidth of 100 MHz for the uplink and the downlink alike to perform communications at maximum transmission rates of 1 Gbps or higher in the downlink and 500 Mbps or higher in the uplink.
Furthermore, Advanced E-UTRA is also discussing measures against sharp increases in traffic due to accesses to the Internet by smartphones and the like. That is, Advanced E-UTRA is discussing an arrangement (offloading arrangement) in which in a case where E-UTRA alone cannot cope with traffic, the concentration of traffic into E-UTRA is avoided by switching traffic from E-UTRA to another access system such as a wireless LAN (WLAN) or WiMAX depending on the situation.
NPL 1 discloses a method in which a terminal apparatus uses ANDSF (access network discovery and selection function) in the procedure for switching from one access system to another. ANDSF is a function for distributing a policy configured by a mobile operator to a terminal apparatus so that the terminal apparatus can select an access system for one or more flows in which the terminal apparatus is communicating or is to perform communication (or for each access point name (APN)).
NPL 1 discloses that radio access network assistant information notified from a base station apparatus to a terminal apparatus and measurement information in the terminal apparatus are used in selecting an access system on the basis of a policy distributed by ANDSF.